Hitherto, the following processes have been employed for making color sheets for color proofs or displays; (1) a process comprising the steps of: (A) imagewise exposing a light-sensitive laminate composed of a temporary support having formed thereon a peelable layer comprising an organic polymer and a light-sensitive resin layer containing a coloring material, (B) developing to form images on the peelable layer, (C) peeling the peelable layer having the image formed, and (D) transferring the layer onto an optional support (see, e.g., Japanese Patent Publication Nos. 15326/71 (corresponding U.S. Pat. No. 3,721,557), 441/74, etc.), (2) a process comprising the steps of: (A) forming images on a layer on a temporary support, (B) superposing the color image-containing layer on the support on the surface of a sheet, and (C) transferring the image-containing layer on the sheet by pressing under heating (see, e.g., Japanese Patent Application (OPI) Nos. 41830/72, 9337/73, 5101/76, etc.) (the term "OPI" as used herein refers to a "published unexamined Japanese patent application"), (3) a process comprising the steps of: (A) transferring images of each color on a temporary image-receiving sheet having a photopolymerizable image-receiving layer prior to transferring the images on a desired sheet, (B) transferring, the images on the desired sheet, and (C) curing the photopolymerizable image-receiving layer by overall light exposure (see, e.g., Japanese Patent Application (OPI) No. 97410/84 (corresponding to U.S. Pat. No. 4,482,625), (4) a process comprising the steps of: (A) transferring an image-carrying layer formed on a transferable light-sensitive material onto an image-receiving sheet composed of a support having formed thereon a layer of an organic high molecular material, and (B) transferring the images on a permanent support (see, e.g., Japanese Patent Application (OPI) No. 27735/87), and (5) a process comprising the steps of: (A) transferring an image-carrying layer formed on a transferable light-sensitive material onto an image-receiving sheet material composed of a support having formed thereon a 1st layer of a 1st organic high molecular material and a 2nd layer of a 2nd organic high molecular material, and (B) transferring the images onto a permanent support (see, e.g., Japanese Patent Application (OPI) No. 189535/86).
In process (1) above, it is required to use an adhesive each time at which the color images are transferred. Hence, there is a drawback in that in the case of transferring images of each color, it is difficult to match the positions of these images without causing positional discrepancy. Further, process (1) above has inferior workability.
In process (2) above, images can be smoothly and uniformly transferred onto a sheet. However, there is a drawback in that the images obtained are reverse in right and left to the original.
In process (3) above, correct images are obtained to the original and the images can be smoothly and uniformly transferred onto a sheet. However, there are drawbacks in that, since in many cases an unavoidably and slightly colored material (substantially colorless materials, e.g., a polymerization initiator, are preferred) is used in the point of light sensitivity for imparting photopolymerization for the photopolymerizable image-receiving layer, the colors of the color images formed on the desired sheet and the color of the background are discolored as a result of the unavoidably and slightly colored materials in the layer. In addition, since the surface is coated by the photopolymerized image-receiving layer, unnecessary luster appears and hence a matting treatment is required.
In process (4) above, since a light exposure is unnecessary after transferring images onto the image-receiving sheet, there is no problem of discoloring by unaboidably and slightly colored materials. However, there is a drawback in that there is unnecessary luster.
On the other hand, in process (5) above, correct images can be smoothly and uniformly transferred, after transferring onto a transferable image sheet material, onto a desirable sheet, such as a metal plate, a plastic film, a cloth, etc. In addition, there are no troubles of discoloring the transferred images on the sheet and causing unnecessary luster on the surface of the images. Furthermore, in process (5) above, neither a post exposure nor matting process is required upon the transfer of the images as compared with process (3). Moreover, in the case of using paper as the desired sheet, the toughness of the paper increases the resemblance thereof to prints. Additionally, images having high whiteness of the non-image portions can be obtained.
However, since the image-receiving sheet which is used in process (5) above is composed of a support having formed thereon a 1st layer of a 1st organic high molecular material and a 2nd layer of a 2nd organic high molecular material, such a sheet is disadvantageous in terms of its productivity.
Furthermore, in process (5) above, the aforesaid 2nd layer may be transferred together with the image-carrying layer (hereinafter simply referred to as an image layer) on a permanent support upon the transfer of the image layer. In this case, it sometimes happens that images formed on the permanent support swell and have unnecessary luster formed thereon.
Thus, it has been desired to develop an image forming process capable of transferring an initial image layer only onto a permanent sheet as correct images.